Made a simple sighting tube for my 20x80 binoculars today. Used a soluble vitamin tube, 2 spring clips and a small bracing bracket which all sit nicely on top my basic binocular mount.

Guessing the view angle is about 5 degrees.

'Discovered' the FOV on my binoculars is 3.5deg not 2.5!! Adjusted optics settings on Starmap Pro. Important stuff for developing my star hops. Still convinced I was looking at 81uma the other night not 83uma (which could have crept into the FOV at 3.5degrees). This may just be wishful thinking as 83 is a mag lower than 81 at mag5.6.

Set up Stellarium on PC - cool piece of software. Managed to add ocular to simulate my bins after a bit of messing around.